As a nonvolatile semiconductor memory, the NAND flash memory is widely known. The NAND flash memory simultaneously stores data of a predetermined size in memory cells. It also simultaneously reads the data of a predetermined size from memory cells.
Blocks having respective functions are mounted on a semiconductor chip to form a system, which enables a semiconductor device to have desired features. Such function blocks include the NAND flash memory and a random access memory (RAM), for example. There is a demand to further accelerate operation of such a system.